Gasification of Iranian walnut shell as a bio-renewable resource for hydrogen-rich gas production using supercritical water technology

Safari, Farid; Tavasoli, Ahmad; Ataei, Abtin

doi:10.1007/s40090-016-0093-9

Cited by 13 publications

(3 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Cellulose is made of glucose subunits that are linked with via β-1,4-glycosidic bonds, while hemicellulose is a branched heteropolysaccharide consisting of C5 sugars (usually xylose and arabinose). 23 Cellulose has high crystallinity and consists of repeating units in linear chains with higher polymerization degree, while the structures of lignin and hemicellulose are amorphous. 24 Hemicellulose contains monomer units such as xylose in a branched, irregular structure and with a lower degree of polymerization.…”

Section: ■ Introductionmentioning

confidence: 99%

“…Since the percentages of each of the main components vary in different biomass and as each component has its own specific characteristics, the behavior of each feedstock under HTC is specific. Cellulose is made of glucose subunits that are linked with via β-1,4-glycosidic bonds, while hemicellulose is a branched heteropolysaccharide consisting of C5 sugars (usually xylose and arabinose) . Cellulose has high crystallinity and consists of repeating units in linear chains with higher polymerization degree, while the structures of lignin and hemicellulose are amorphous .…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Prediction of Hydrothermal Carbonization with Respect to the Biomass Components and Severity Factor

et al. 2019

View full text Add to dashboard Cite

In recent years, hydrothermal carbonization (HTC) has been introduced as an attractive method for converting biomass into value-added products. The complex reaction chemistry and variable composition of biomass have, however, been barriers to find general equations for describing the HTC process. The goal of this study is to establish a link between the composition of biomass and the expected hydrochar from HTC. Based on the experimental design found from response surface methodology, the biomass components, namely pure cellulose, hemicellulose, and lignin, were submitted in different combinations into 39 HTC experiments with severity factors (SFs) of 3.83, 5.01, and 6.19. Using the experimental data, an attempt was then made to predict the mass yield, higher heating value (HHV), carbon content (C%), and energy recovery factor of the hydrochars according to the biomass composition and the process severity. The results revealed that the interactions between the biomass components do not have a major effect on the hydrochar characteristics, whereas the interaction between cellulose and SF is the most significant. Moreover, it was shown that, after the lignin content, the hemicellulose content has the highest positive impact on HHV and C% of the hydrochar. An optimization study showed that, with a focus on minimizing the SF while the HHV is maximized, biomass with a cellulose content of 40%, hemicellulose of 35%, and lignin of 25%, under the severity of 4.41 will be the most suitable case for HTC treatment. Finally, a comparison between the predictions and the experimental data in the literature suggests that the proposed equations can provide a good evaluation on the HTC of several biomass feedstocks, especially when the amount of ash and extractives are low.

show abstract

Section: ■ Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Prediction of Hydrothermal Carbonization with Respect to the Biomass Components and Severity Factor

et al. 2019

View full text Add to dashboard Cite

show abstract

“…HCl as a catalyst promoted the formation of levulinic acid, but the conversion rates were very low [41]. In another few studies, the shells of pistachios, walnuts and other nuts were used to generate hydrogen-rich gas with supercritical water as a medium [42][43][44].…”

Section: Introductionmentioning

confidence: 99%

The Conversion of Pistachio and Walnut Shell Waste into Valuable Components with Subcritical Water

Čolnik,

Irgolič,

Perva

et al. 2024

Processes

View full text Add to dashboard Cite

Pistachio and walnut shells accumulate in large quantities as waste during food processing and represent a promising lignocellulosic biomass for the extraction of valuable components. Subcritical water technology was used as an environmentally friendly technique to study the extraction of active ingredients and other valuable degradation products from walnut and pistachio waste. Subcritical water extraction (SWE) was carried out under different process conditions (temperature (150–300 °C) and short reaction times (15–60 min)) and compared with conventional extraction using different organic solvents (acetone, 50% acetone and ethanol). The extracts obtained from pistachio and walnut shell waste are rich in various bioactive and valuable components. The highest contents of total phenols (127.08 mg GA/g extract at 300 °C for 15 min, from walnut shells), total flavonoids (10.18 mg QU/g extract at 200 °C for 60 min, from pistachio shells), total carbohydrates (602.14 mg TCH/g extract at 200 °C for 60 min, from walnut shells) and antioxidant activity (91% at 300 °C, for 60 min, from pistachio shells) were determined when the extracts were obtained via subcritical water. High contents of total phenols (up to 86.17 mg GA/g extract) were also determined in the conventional extracts obtained with ethanol. Using the HPLC method, sugars and their valuable derivatives were determined in the extracts, with glucose, fructose, furfurals (5-hydroxymethylfurfural (5-HMF) and furfural) and levulinic acid being the most abundant in the extracts obtained by subcritical water. The results show that subcritical water technology enables better exploitation of biowaste materials than conventional extraction methods with organic solvents, as it provides a higher yields of bioactive components such as phenolic compounds and thus extracts with high antioxidant activity, while at the same time producing degradation products that are valuable secondary raw materials.

show abstract

Exergetic, exergo-economic, and exergo-environmental analyses of a trigeneration system driven by biomass and natural gas

Jalili

Ghasempour

Ahmadi

et al. 2021

J Therm Anal Calorim

View full text Add to dashboard Cite

Gasification of Iranian walnut shell as a bio-renewable resource for hydrogen-rich gas production using supercritical water technology

Cited by 13 publications

References 33 publications

Prediction of Hydrothermal Carbonization with Respect to the Biomass Components and Severity Factor

Prediction of Hydrothermal Carbonization with Respect to the Biomass Components and Severity Factor

The Conversion of Pistachio and Walnut Shell Waste into Valuable Components with Subcritical Water

Exergetic, exergo-economic, and exergo-environmental analyses of a trigeneration system driven by biomass and natural gas

Contact Info

Product

Resources

About